President Barack Obama's administration believes Israel's delegation to next week's nuclear security summit in Washington will be "robust," despite Israeli Prime Minister Benjamin Netanyahu decision not to attend, a top official said on Friday.

"We obviously would like to have the prime minister but the deputy prime minister will be leading the delegation and it will be a robust Israeli delegation," U.S. National Security Adviser General Jim Jones told reporters traveling on Air Force One.

He also said that relationships between the U.S. and Israel are "ongoing, fine and continuous."

Secretary of State Hillary Clinton on Friday welcomed the Israeli delegation's participation in the conference by saying, "Israel shares with us a deep concern about Iran's nuclear ambitions and also about the threat of nuclear terrorism."

Prime Minister Benjamin Netanyahu canceled his planned trip to Washington, where he was scheduled to participate in a nuclear security summit hosted by U.S. President Barack Obama, government officials said.

Intelligence and Atomic Energy Minister Dan Meridor will take Netanyahu's place in the nuclear summit.

Obama has invited more than 40 countries to the summit, which will deal with preventing the spread of nuclear weapons to terrorist groups.

Netanyahu was due to arrive in Washington on Monday evening and was set to take part in three or four conference sessions the following day, before returning to Israel on Wednesday.

Officials said the PM canceled the trip over fears that a group of Muslim states, led by Egypt and Turkey, would demand that Israel sign up to the international Nuclear Non-Proliferation Treaty, or NPT.

A senior government official told Haaretz that that Israel was "disappointed" with developments in the run-up to the conference.

"The nuclear security summit is supposed to be about dealing with the danger of nuclear terror," the official said. "Israel is a part of that effort and has responded positively to President Obama's invitation to the conference."

The official added: "But that said, in the last few days we have received reports about the intention of several participant states to depart from the issue of combating terrorism and instead misuse the event to goad Israel over the NPT."

The White House said it had been informed Netanyahu would not attend the summit and that Deputy Prime Minister Dan Meridor would lead the Israeli delegation.

"We welcome Deputy Prime Minister Meridor's participation in the conference. Israel is a close ally and we look forward to continuing to work closely on issues related to nuclear security," said Mike Hammer, White House National Security Council spokesman.

In New Orleans, hundreds of party loyalists at the Southern Republican Leadership Conference applauded when they were informed Netanyahu had just canceled his visit to Washington.

At the gathering, Liz Cheney, daughter of former U.S. Vice President Dick Cheney, blasted Obama for his "shabby" treatment of Netanyahu at the White House recently, saying it was "disgraceful".

She added: "Israel is our strongest ally in the Middle East and one of our strongest allies anywhere around this globe. And President Obama is playing a reckless game of continuing down the path of diminishing America's ties to Israel."

One hundred eighty-nine countries, including all Arab states, are party to the NPT. Only Israel, India, Pakistan and North Korea are not.

Israel is widely believed to have nuclear weapons but operates a policy of 'nuclear ambiguity', never publicly confirming or denying their existence.

Many Muslim countries have voiced alarm at alleged nuclear programs in Israel and Iran, and have repeatedly called for an agreement to ban nuclear weapons from the region.

In late March the Arab League called for a Middle East free of nuclear weapons during a closed-door session, calling for a review of the 1970 NPT in order to create a definitive plan for eliminating nuclear weapons .

They also called on the UN to declare the Middle East as a nuclear-weapons-free region.